As shown in Non-Patent Document 1 http://www.to-hatsu.cojp/products/sc_built.html and in FIG. 1, a spiral conveyor 1 is so designed that a conveyance spiral member 3 like a coil spring is received in a tray 2 and driven by a drive means 4 including a motor with a deceleration mechanism to be rotated at a low speed in a predetermined direction, thereby conveying chips 5 thrown into the tray 2 in a predetermined direction within the tray 2, while doing solid-liquid separation, which are then discharged toward a discharge duct 6 connected to the tray 2. Cutting fluid 7 is thrown into the tray 2 together with the chips 5, which will fall by gravity during conveyance to be separated from the chips and collected in a cutting fluid tank 8 positioned beneath the tray 2. Such spiral conveyor has been widely used in various machine tools, because it is capable of smoothly conveying chips having various shapes, sizes and materials, from largely-expanded long-chain-shaped continuous chips to needle-like fine chips, it has a simple structure and may be manufactured and provided at a low cost, it will achieve smooth conveyance while preventing the chips from being clung or entangled with each other, it will achieve long-distance conveyance of the chips in a process system wherein various machine tools are connected to each other, it is possible to efficiently separate and collect the cutting fluid adhered to the chips, etc.